Transient Plasma Systems, Inc. (TPS) developed and demonstrated an advanced transient plasma ignition technology that improves efficiency and competitiveness of heavy-duty natural gas engines. The transient plasma ignition system produces high peak power, low energy, nanosecond duration electrical pulses that generate a highly reactive plasma instead of the thermal spark or arc generated by conventional ignition systems. Before this project, TPS conducted more than 20 single-cylinder engine tests with multiple partners to demonstrate the capability of this advanced ignition technology to extend exhaust gas recirculation (EGR) limits, enabling significant gains in brake thermal efficiency. This project focused on scaling this technology to drive multiple engine cylinders from a common power supply using solid-state components that are capable of compliance with automotive grade requirements. TPS partnered with Argonne National Laboratory to conduct instrumented engine experiments to investigate the scalability of results from past single-cylinder tests to a commercially available, heavy-duty multi-cylinder engine. All engine testing was conducted on the Cummins Westport, Inc. ISX12N, a production on-road natural gas engine available for heavy-duty trucks. Engine testing at Argonne National Laboratory demonstrated a more than 25 percent extension of EGR dilution tolerance with stable engine operation, 30 percent reduction in NOx emissions, greater than 10 percent reduction in CO emissions, and greater than 2 percent relative improvement in efficiency without updated fuel maps. Further optimization with updated fuel maps would enable additional efficiency gains from using the transient plasma ignition system. Transient plasma ignition technology can be integrated with existing natural gas engines to accelerate their adoption over conventional diesel engines, resulting in greenhouse gas and criteria pollutant emission reductions.
